Missing some settings in main server configuration file

[Enet4]

In some of the past reiterations of the DICOM storage system, we added adjustable properties that could be overridden via JVM properties. (#503 #453) Now, we should not forget to make them available in server.xml, which is currently the recommended place for all server settings related to DICOM storage and indexing.

A non-exhaustive list of parameters which would be nice to have in server settings:

• dicoogle.taskManager.nThreads and dicoogle.taskManager.nQueryThreads
• dicoogle.index.async
• Check whether any of these parameters are missing: dicoogle.cstore.maxScpAssociations dicoogle.cstore.acceptTimeout dicoogle.cstore.connectTimeout dicoogle.cstore.dimseRspTimeout dicoogle.cstore.idleTimeout dicoogle.cstore.appendMaxPDU dicoogle.cstore.appendMaxPDU dicoogle.cstore.retrieveRspTimeout